Therapy of experimental herpes simplex encephalitis with aciclovir in mice

This report is concerned with the capacities of aciclovir to protect mice challenged intracerebrally with multiple lethal doses of type 1 herpes simplex virus and to control multiplication of this virus in the brain. With treatment initiated 12 hr after inoculation and continued for 4 consecutive days, aciclovir administered subcutaneously in daily doses ranging from 40 to 100 mg/kg led to 21-day survival rates of from 33 to 73% and reduced virus titers by 1 to 1/2 x 4 logs on postchallenge day 8. The therapeutic accomplishments of the 100-mg/kg doses of aciclovir were comparable to those of 1,000-mg/kg doses of vidarabine (9-β-D-arabinofuranosyladenine); however, as measured by impact on body weight, aciclovir was better tolerated than vidarabine at these similarly effective doses.